In the prior art it is well known to use manual and pushbutton tuning in radio receivers and the use of a clutch mechanism for decoupling the manual tuning during pushbutton operation is described, for example, in U.S. Pat. No. 3,906,806 to Harlan. Furthermore, the use of a "memory" cams associated with each of the pushbuttons for selecting a desired frequency is described in U.S. Pat. No. 3,727,156 to Olah.
A problem associated with the operation of these types of tuning devices is that the mechanisms are complex in that they require many moving parts causing lost motion which has resulted in a decrease in the quality listening entertainment on a receiver. Furthermore, because of the complex mechanisms it is a problem to build a small compact unit with a low profile to provide the necessary functions of operation desired in a car radio receiver. An attempt at eliminating lost motion within a flat pack tuning device is the tuning device described in Wilkinson U.S. Pat. No. 3,946,344. However, this tuning device has a plurality of pin members which must be positioned in V-shaped apertures formed in an elongated slide bar and, therefore, misalignment of the pins and slide bar apertures causes a lost motion resulting in fluttering in the tuning device.